membersegmentaffiliations allows duplicated affiliations

[joanagmaia]

select * from membersegmentaffiliations where memberid='0d04e2ba-9e2c-41e2-8789-5bba50addcd5' and segmentid='0b833da9-ffe6-458d-b9d2-a709e6b81b00';

Returns 3 affiliations exactly with the same values.

We shouldn't allow affiliations for the same project to have the exact same period